Numerical study of broaching attracting basin;

Study of broaching in following sea and manoeuvre countermeasure;

The wave-induced water particle velocity around a ship under the broaching-to condition is expressed in term of an equivalent yaw rate so that the hydrodynamic derivative for ship manoeuvre motion in calm water can be used for estimation of the wave-induced lifting moment.

From this, it is clarifled that the occurrence of broaching-to phenomena in following seas is induced by a concerted action of the wave environment and ship s navigation, including the ratio of wave length to ship length, wave slope, ship s speed, etc.

The article introduces the mining coal working face false inclines the necessity which the arrangement,returns picks,flings the slanting plan through the formulation science,takes the efficient technical measure,solves the irregular mining coal working surface to return picks in the process to fling the slanting question,returns to the similar working face picks has the certain model function.

A special concept,named "shuaigao" which means height of the material stack behind roller,is suggested.

It often creats telescope,dish,wrinkle and break dishout with a lot of waste materials and fires.